/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */


package org.apache.tomcat.util.modeler;


import java.util.List;

import javax.management.ObjectName;

/**
 * Interface for modeler MBeans.
 * <p>
 * This is the main entry point into modeler. It provides methods to create
 * and manipulate model mbeans and simplify their use.
 * <p>
 * Starting with version 1.1, this is no longer a singleton and the static
 * methods are strongly deprecated. In a container environment we can expect
 * different applications to use different registries.
 *
 * @author Craig R. McClanahan
 * @author Costin Manolache
 * @since 1.1
 */
public interface RegistryMBean {

    /**
     * Invoke an operation on a set of mbeans.
     *
     * @param mbeans    List of ObjectNames
     * @param operation Operation to perform. Typically "init" "start" "stop" or "destroy"
     * @param failFirst Behavior in case of exceptions - if false we'll ignore
     *                  errors
     * @throws Exception Error invoking operation
     */
    public void invoke(List<ObjectName> mbeans, String operation, boolean failFirst)
            throws Exception;

    /**
     * Register a bean by creating a modeler mbean and adding it to the
     * MBeanServer.
     * <p>
     * If metadata is not loaded, we'll look up and read a file named
     * "mbeans-descriptors.ser" or "mbeans-descriptors.xml" in the same package
     * or parent.
     * <p>
     * If the bean is an instance of DynamicMBean. it's metadata will be converted
     * to a model mbean and we'll wrap it - so modeler services will be supported
     * <p>
     * If the metadata is still not found, introspection will be used to extract
     * it automatically.
     * <p>
     * If an mbean is already registered under this name, it'll be first
     * unregistered.
     * <p>
     * If the component implements MBeanRegistration, the methods will be called.
     * If the method has a method "setRegistry" that takes a RegistryMBean as
     * parameter, it'll be called with the current registry.
     *
     * @param bean  Object to be registered
     * @param oname Name used for registration
     * @param type  The type of the mbean, as declared in mbeans-descriptors. If
     *              null, the name of the class will be used. This can be used as a hint or
     *              by subclasses.
     * @throws Exception Error registering MBean
     * @since 1.1
     */
    public void registerComponent(Object bean, String oname, String type)
            throws Exception;

    /**
     * Unregister a component. We'll first check if it is registered,
     * and mask all errors. This is mostly a helper.
     *
     * @param oname The name used by the bean
     * @since 1.1
     */
    public void unregisterComponent(String oname);


    /**
     * Return an int ID for faster access. Will be used for notifications
     * and for other operations we want to optimize.
     *
     * @param domain Namespace
     * @param name   Type of the notification
     * @return A unique id for the domain:name combination
     * @since 1.1
     */
    public int getId(String domain, String name);


    /**
     * Reset all metadata cached by this registry. Should be called
     * to support reloading. Existing mbeans will not be affected or modified.
     * <p>
     * It will be called automatically if the Registry is unregistered.
     *
     * @since 1.1
     */
    public void stop();
}
